Hi @Kash80 ,
Does anyone else have the same issue in your organization?
Have you tried to use another applications (chat application) to see if you received the same message notification in IOS?
If you make a call on PC, can you receive the call in IOS device?
If this issue can be reproduced by another applications, we think this issue is more related to IOS system settings, it is a good way for you to contact Apple supporter to solve this issue.
In addition, we recommend you try to change your “show previous” settings to “Never” to see if this issue can be fixed.
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